Hey, sorry I've been gone so long. I'm back now, but will probably only be able to visit the sight about once a week due limited time. I will try to answer one post on this thread a week and do some reading on ancient realms, among other things. So first question.

Quote Originally Posted by Great Dragon View Post
DMG EXP Calculations. Pages 82-84.
Creating a Monster DMG pg 283.

Not having a physical copy is a pain!!

Ok, the Pegasus is a CR 2.
And, the Unicorn is a CR 5.

So would the Legendary Alicorn be a CR 8?
Move 50 (1,000 lb limit) Fly 50. (500 lb limit)

Innate Telepathy 60 feet.
At Will: Viscous Mockery, Eldritch Blast (Radiant with Repelling), and Raise Dead.
Once a day: Sickening Radiance as Aura. (Suggested by DM Peter)

Save DC 14.
3 Spell slots: Phantasmal Killer, Greater Invisibility, Counterspell.

Healing Touch 3/day for 5d8 HP each.
Teleport 3 times a day.

Attacks are considered magical.
+8 Hit 2d8+4 blunt (x2 hooves) and 2d10 Pierce (Horn).

Same Legendary Actions as Unicorns.
I tried to answer this before, but couldn't find the necessary information; I still couldn't. I really don't know about calculating the challenge ratings of monsters. I just go off of what is similar, what are the differences between this and the similar creature and what level of a party would consider it a normal challenge. So especially since (but even if I could) I can't see the HP of this creature, I really don't know what CR it would have.

But, CR aside, this looks like another well designed creature. Sorry for my lack of useful information.